1. Prior Art
When fabricating a carrier from a paperboard blank, opposite ends of the blank are conventionally attached to each other by glue or by mechanical locks to form the bottom panel of the carrier. In the case of a wrap around carrier, flaps located on the ends of the blank typically are overlapped and engaged with one another by mechanical locks formed in the flaps to form the bottom panel of the carrier. Since the bottom panel must maintain its integrity throughout the use of the carrier, it is essential that the locking system be capable of supporting the weight of the packaged articles, and remain engaged during shipping and handling of the constructed carrier.
One approach to provide a stable mechanical lock assembly utilizes both primary and secondary locks. An example of such locking system is disclosed in U.S. Pat. No. 5,443,203 to Sutherland.
Bottles constructed out of PET that have petaloid bases are difficult to package in a wrap around carrier that produces a tight package. These petaloid bottles have from four to six toes so the wrap usually has a pair of heel doors to form a heel retaining assembly which allows one of the toes to project through the aperture formed by opening the heel doors. This system works fine if the toe is centered in the aperture formed by opening the heel doors. It is difficult to align the petaloid bottles so that a toe is centered in this aperture. If the toe is not centered it may tear open the heel retaining assembly resulting in a loose wrap around carrier.